Interlocking system for railroads



April 5, 1932. ALANGDON INTERLOCKING SYSTEM FOR RAILRCADS Filed July 11,1930 INVENTOR fl. law/W lt atenterll rhprr 5, i932 ttttl STATES PATENTorator:

WG'DUN, @I ROCHESTER,

:unw YORK, Assmiron '10 GENERAL RAILWAY SIGNAL COMPANY, OF ROCHESTER,NEW YORK INTEBLOCKING SYSTEM FOR RAILBOADB Application filed InIy II',

switch machine and its assoclated interlock inc.

in interlocking systems of the mechanically interlocked lever type, andin types of sys- V terns in which the levers are locked by suit- ?lllable approach looking or detector locking means, the operator is ofcourse not able under unsafe conditions to move the lever, and tor thatreason cannot tentatively set up an operating condition which may laterbecome ezd'ective due to the clearing up of the conditions "whichformerly locked the lever. In

other words, in systems such as just mentinned, the operator cannotinitiate a control until it is proper for such control to become 5mehective. in accordance with the present invention it is proposedtoleave' the levers free and unlocked at all times, and in order toprovide the necessary interlocking and approach or detector locking,such as may be required Fill to carry out such interlocking electricallyand irrespective of movement of the lever, it is proposed to providesimple electrical means tor eitecting such approach and detector lockrug control, which requires movement of the till control leverconcurrently with favorable approach and detector locking conditions,and this is carried out without manually restraining the movement of thecontrol lever.

Another object of the present invention is W to provide a simple andnovel organization of.

parts and circuits to. obtain the necessary and desirable indications,such as means for indicating the electrically unlocked condition oi thelever, and the out of correspondence W condition of the lever withrespect to the distaut trafioc controlling device it controls, as wellas other suitable means for preventing the control of the trafficcontrolling devices under unsafe conditions or by the application oi"unauthorized current.

More specifically it is proposed to control 1880. Serial 1T0. 467,233.

chine to be controlled by the associated lever only under properapproach traffic'and route conditions, including suitable means forpreventin operation of such switch machine event ough route conditionsand approach conditions clear up and the operator has left the lever insuch operated position, and to render said suitable means inactive assoon as the distant traflic controlling device or switch machine hasassumed a POSltlOIl COII'BSPOIlding to that of the lever for controllingthe same.

Other objects, purposes and characteristic features of the presentinvention will in part be obvious from the accompan in drawing and willin art be more speci cal y pointed out hereina er.

.In describing the invention in detail reference will be made to theaccompanying drawing, in which the portion in the dotted rectanglerepresents the apparatus located in the interloc ing tower, and theremaining apparatus illustrated is located at a distant track switch onthe railway system,

Structure Referring to the drawing, the track rails 1 of a railwaysystem have been shown divided into blocks by insulating joints 2, toprovide the usual track circuits, of which the 'detector track circuithaving the track relay DR and a track battery 3 and the approach sectionhaving the track relay TR and a track battery l only have been shown.The siding or diverging route has been indicated by track rails 5connected to the main track through the medium of the track switch S,which track switch is operated by-a switch machine SM. The switchmachine SM is controlled by the snap action, .or stick type, relay CR,which relay after it is operated to one of its operated positionsremains there until it is electrically or manually operated to the otherposition, even though it is deenergized in the mean time.

In the interlocking tower, conventionally shown by the dotted rectangleT, is located a lever L having pole changer contacts -11 and 12-14, ofwhich the contacts 10 and 11 control the flow of current to the polarcontrol relay CR, and of which the pole changer con-' S and the switchmachine SM, whereby the relaylR will assume one polar position namelythe full-line position when the switch S assumes the main track fullylocked position and will assume the other polar position namely thedotted position when this track switch S assumes the take-sidinglocked-u condition.

Associated with the lever L in the tower T is also a' stick relay R,which relay can only be picked up when the lever L is in correspondencewith the switch machine SM and with approach conditions manifested bythe contact 20 of the track relay DR and the contact 21 of the trackrelay. TR are closed, and with the contacts 22 closed manifesting thatall of the conflicting signals are at stop, and this stick relay SR whenonce picked up will only remain up so long as said contacts 20, 21 and22 remain closed.

The tower apparatus also includes a lock relay LR which is normallydeenergized and normally short circuits the control relay CR through theshunting wires 23 and 24. This lock relay LR can only be picked up whenthe stick relay SR is energized and the lever L is out of'correspondencewith the distant traflic controlling device or switch machine SM.as'manifested through the indicating relay IR. There are also providetwo indicating lamps for each of the levers L, the lamp 00C of whichindicates when illumi nated that the lever L is out of correspondencewith the distant traflic controlling device, and the lamplUL of whichwhen illuminated indicates t at the lever is electrically unlocked .andmay, u on being moved, control its associated tra c controlling device.7

Even though the contacts 22, which are closed if the signals ofconflicting routes are at stop and which have been shown included in theick up and stick circuit for the stick relay SR, thus gareventingcontrol of the switch machine M under conflicting route conditions, havebeen illustrated, it is to be understood that these contacts 22 may beomitted and suitable local interlocking between the signals and theswitch machine may be employed, this local interlocking acting eitherupon the control relay CR or acting to prevent operation of the switchmachine SM under dangerousconditions by suitable contacts included inthe normal and the reverse circuits N and R of the switch machine SM.Also, in spite of the fact that I the invention has been shown appliedto a .switch machine, it is to be understood that the 1' same principlesunderlying the present invention ma be applied to control circuits forcontrol 'n derails, wayside semaphore or-light signals, mentioned thevarious elements of the system, it is deemed expedient to consider theoperation of the system, this in order to more clearly point out t eoperating characteristics and the features of safety vided by thesystem.

Operation and facility pro- Let us assume that the operator in the towerT wishes to operate the track switch S and the like. Having now to thetake-siding position, and .in order.

to do so moves the lever L to the dotted posi-- ,tion at a time when thedetector track circuit including the track relay DR and .the approachsection including the track relay TR are unoccupied and the contacts 22are closed manifesting that the signals of conflicting routes are atstop. Under the conditions assumed the stick relay SR is energizedthrough the following. circuit :-beginning at the terminal rent, such asa atter front contact 20 of the track relay DR,w1re 30, front contact 21of the track relay TR, wire. 31, contacts 22,

wires 32 and 33, stick contact 34 of the relay SR, wires 35 and 36,winding of the stick relay SR, and to the other terminal C of the samebattery. Also, with the lever L now assuming the dotted position thelock relay LR is energized through the following circuitz-beginning atthe terminal B, front contact 20 of the relay DR, wire 30, front contact21 of the relay TR, wire 31, contacts 22, wires 32, 40 and 41, contact15 of the indicating relay IR assuming the normal osiof a suitablesource of curtion, wires 42 and 43, contact 12 of the ever L assumingthe dotted position, wire 44, front contact 45 of the stick relay SR,wire 46, windin of the lock relay LR to the other terminal. of the samebattery.

Picking up of the lock relay LR removes the shunting wires 23 and 24-from the line circuit leadingto the control relay CR and with thecontacts 10 and 11 of the lever sumin their dotted position the controlrelay C isenergized. through the following circuit :beginning at thepositive terminal of the battery 50, wires 47 and 48, contact 10 of thelever L, wire 49, front contact 51 of the lock relay LR, line wire 52,winding of the control relay CR, line wire 53, front contact 54 of therelay LR, wire 55, contact 11 of the lever L, wires 56 and 57, and backto the battery 50. Flow of current inthe circuit just traced operatesthe control relay OR to its left hand otted position, therebyop- Las- Ycrating the switch machine SM to the take- 1 siding position througlhthemedium of its reverse circuit throu Y the reverse wire R andthe contact58 o the control relay CR.

dti

till

As soon as the switch machine SM has been operated to the take-sidingositionthe contact 1617 within the switc machine, or in a suitableswitch box, are operated to the dotted position, thereby reversin thepolarity of current applied to the in icating relay IR and operatingthis rela IR to its dotted position, through the me ium of the linewires 59 and 60. With the indicatcontact 20 of the relay DR, wire 30,contact 21, wire 31, contacts 22, wires 32, and 41, contact 15 thenassuming theiull line posi-. tion, wires 42 and 43, contact 12 of leverL assuming the dotted position, wire 59, indicating lamp U00, to theother terminal C of said source. "The unlocked lever lamp UL is ofcourse illuminated so long as the contacts 20, 21 and 22 are closed, andthe circuit for this lamp UL, readily traced in the drawings, andincluding the wire is otherwise intact. It is thus seen that with thelever L out of correspondence with the indicating relay ill and with thestick relay SR energized the lock relay LR is energized so long as thisout of correspondence and safe route and approach locking conditionexists, and that the lock relay LR is deenergized as soon as theindicating relay 1R gets into correspondence with the lever L.

Let us now see what the effect would be if the operator operated thelever L at a time when the unlocked lamp UL is dark as a result of theopening of one of the contacts 20, 21 or 2:2. Such opening of one ofthese con-' tacts 20, 21 or 22 will of course extinguish the lamp UL,advising the operator that he must not operate the lever, and willdeenergize the stick relay SR. If the operator under this condition wereto operate the lever, say from the normal to the dotted position, thelock relay LR would not be energized because the contact 45 of the stickrelay SR is open. Furthermore, if the operator left the lever L in thedotted position and traffic or route conditions cleared up later, sothat the contacts 20, 21 and 22 are then all closed, the unlocked leverlamp UL would be again illuminated, as would also the out ofcorrespondence lamp OOC, but the stick relay. SR would remaindeenergized, because the pickup circuit for this stick relay, andincluding the wire 61 and the contact 14 of the lever L would beincomplete, because the contact 14 of the lever L and the contact 15 ofthe relay 1B are out of correspondence, so that the multiple part of.this circuit including the wires 42 and 39 in multiple is open, and theTy I stick relay SR cannot be picked up.

The illumination of the out of correspondence lamp 00G under theconditions assumed, would of course direct the attention .of theoperator to the fact that his lever L is out of correspondence with theswitch machine SM, in response to which the operator would return thelever L to its normal position under which condition the, stick relay SRwould be picked up through the following its left hand full lineposition, wire 42,

contact 14 of the lever L, wires 61 and 36, winding of the stick relaySR, and to the other terminal C of the same battery. As soon as thestick relay. SR assumes its energized position the closure of its stickcontact 3 1 shunts the'hontacts 14 and 15 and the as- DR, wire 30, frontcontact 21 of the sociated wires 39, 40, 41, 42 and 61, so. that thestick relay SR remains stuck'up through its stick circuit heretoforetraced so long as traific and route conditions are favorable, from whichit'is apparent that the switch machine SM may be operated in response tomovement of the lever L back to the dotted position.

Although the lock relay LR has been shown slow acting, this relay may berather quick acting, in that this relay is not deenergized until theoperating function has been com pleted in its entirety. On the otherhand, this relay LR is preferably slightly slow acting so' that it willnot respond to an instantaneous or transient application of currentthereto.

Having thus shown and described one pa 1'- ticular combination ofcircuits and devices for carrying out the underlying principles of thepresent invention, namely the provision of means including a lever forcontrolling a distant trafiic controlling device in too which the levermust be operated concurrently with safe traific approach locking androute conditions, and if the lever is operated under such safeconditions the control circuit for controlling the distant trafiiccontrolling device is again broken and the control circuit is shortcircuited to prevent interference due to the application of unauthorizedcurrent as soon as the distant traffic controlling device gets intocorrespondence with the lever, it is desired to be understood that theparticular system illustrated has been selected for the purpose ofdisclosing the principles of the present invention and the advantagesresulting therefrom, and has not been selected with additions may bemade to adapt the invention to the particular problem encountered inracticing the same, all without departing rom the s irit or scope of theinvention'or the idea means underlying the same,-except as demanded bythe scope of the following claims. I

What I claim as new is 1. In an interlocking system for railroads;

. the combination with a distant tragic controlling device; of a freemechanica nonlockable lever for controlling such tra 0 controllingdevice but normally ineflfective to permit said trafiic controllingdevice being controlled by said lever; and other means for permittingcontrol of said traffic controlling device by said lever which requiresmovement of said lever when trafiic conditions are proper comprising; arelay which must "be energized to permit control of said trafliccontrolllng device by said lever, and means for energlzing said relayefi'ective only if trafiic conditions are proper and said lever and saidtraflic controlling device are out of correspondence.

2. In an interlocking system for railroads;

' the combination with a distant traffic controlling device; of a freemechanically nonlockable lever for controlling such trafiic controllingdevice but normally inefiective to permit said traffic controllingdevice being controlled by said lever; and other means for ermittingcontrol of said traific controlling device by said lever which requires.4 movement of said lever when traific and route conditions are propercomprising; a relay which must be energized to permit con trol of saidtraflic controlling device by said lever, and means for energizing saidrelay eifective only if trafiic and-route" conditions are proper andsaid lever and said traflic controlling device are out ofcorrespondence.

3. In an interlocking system for railroads;

the combination with a distant trafiic controlling device; of a freemechanically .nonlockable lever for controlling such traific controllingdevice but normally 'ineflective to permit said traflic controllingdevice being controlled by said lever; and other means for permittingcontrol of said traflic controlling device by said lever which requiresmovement of said lever when traific conditions are proper comprising; arelease relay which must be energlzed to permit control of said trafliccontrolling deviceby'said lever, a stick relay which can only be pickedup when trafiic and route conditions are favorable and when said leverand said traflic controlling device assume corresponding positions andwhich will remain stuck up rrespe'ctiv'e of whether said lever andtrafiic controlling device assume corr ondin positions, and a circuitfor said :Zliease re ay including a front contact of said stick relay.

4. In an interlocking s stem for railroads; the combination with adlstant traflic controlling device; of a free mechanically non-lockablelever for controllin such traflic controlling device but normal yineflective to permit said trafiic controlling device being controlledby said lever; and other means for permitting control of said trafliccontrolling device by said lever which requires movement of said leverwhenftraflic conditions are proper comprising; a release relay which somust be ener ized to permit control of said trafiic contro lin device bysaid lever, a stick relay whic can only be picked up when traflic androute conditions are favorable and when said lever and said traflic con-35 trolling device assume correspondingpositions and which will remainstuck up 1rrespective of whether said lever and trafiic controllingdevice assume corresponding positions, and a circuit for said releaserelay including a front contact. of said stick relay and contacts closedwhen said lever and said t raflic controlling device are out ofcorrespondence.

5. In an interlocking system for railroads; the combination with adistant traflic controlling device; of a free mechanicall nonlockablelever for controlling such tra 0 controlling device but normallyinefiective to permit said traflic controllin device being no controlledby said lever; an other means for permitting control of said trafiiccontrolling device by said lever which requires movement of said leverwhen traflic conditions are proper comprising; a relay which must beenergized to permit control of said traflic controlling device by saidlever, means for energizing said relay efiective only if trafiicconditions are proper and said lever and said traific controlling deviceare out of no correspondence, and means for indicating when traflic androute conditions are proper.

6. In an interlocking system for railroads; the combination with'adistant traflic controlling device; of a free mechanically nonlockablelever for controlling such trafiic controlling device but normallyineffective topermit said traflic controlling device being controlled bysaid lever; and other means for permitting control of said trafiiccontrolling device by said lever which requires movement of said leverwhen trafiic and route conditions are proper comprising; a relay whichmust be energized to permit control of said trafiic controlling deviceby said lever, means for energizing said relay efiective only if trailicand route conditions are proper and said lever and said trafliccontrolling device are out of correspondence, and means for in- 13dicating when trafiic, and route conditions are proper. i

7., In an interlocking system for rallroads;

the combination with a distant traflic controlling device; of a freemechanicall nonlockable lever for controlling such tra controllingdevice but normally ineffective to permit said traflic controllingdevice being controlled by said lever; and other means for permittingcontrol of said traiiic controlling device by said lever which requiresmovement of said lever when trafllc conditions are proper comprising; arelease relay which must be energized to permit control of said traficcontrolling device by said lever, a stick relay which can only be pickedup when traffic and route conditions are favorable and when said leverand said traific controlling device assume corresponding positions andwhich will remain stuck up irrespective of whether said lever andtrafiic controlling device assume corresponding positions, a circuit forsaid release relay including a front contact of said stick relay, andmeans for indicating when said lever and said traflic controlling deviceassume non-corresponding positions.

8'. ln an interlocking system for railroads; the combination with adistant trailic controlling device; of a free mechanically-nonlockablelever for controlling such trailic controlling device but normallyineffective to permit said traific controlling device being controlledby said lever; and other means tor permitting control ofsaid trafliccontrolling device by said lever which requires movernent of said leverwhen traific conditions are ill tilt

proper comprising; a release relay which must be energized to permitcontrol of said trafiic controlling device by said lever, a stick relaywhich can only be picked up when trafiic and routeconditions arefavorable and when said lever and said traific controlling device assumecorresponding positions and which will remain stuck up irrespective ofwhether said lever and traffic controlling device assuming correspondingpositions, a circuit for said release relay including a front contact ofsaid stick relay and contacts closed when said lever and said traificcontrolling device are out of correspondence, and means for indicatingwhen said lever and'said traffie controlling device assumenon-corresponding positions.

9. In an interlocking system for railroads; the combination with adistant trafiic controlling device; of a free mechanically nonlockablelever for controlling such trafiic controlling device but normallyinefi'ective to permit said trafiic controlling device being controlledby said lever; and other means for permitting control of said traificcontrolling device by said lever which requires movement of said leverwhen tr'ailic conditions are proper comprising; a release relay whichmust be ener zed to permit control of said traflic contro ling device bysaid lever, a stick rela which can only be picked u when traflic anroute conditions are favora 1e and when said lever and said tra-fiiccontrollin device assume corresponding positions an which will remainstuck up. irrespective of whether said lever and traflic controllingdevice assume corresponding positions, a. circuit for said release relayincluding a front contact of said stick relay and contacts closed whensaid lever and said traflic controlling device are out ofcorrespondence, and means for indicating when trailic and route.conditions are favorable,

10. In an interlocking system for railroads; the combination with adistant traflic controlling device; of a free mechanically non-lockablelever for controlling such trafiic controlling device but normallylneife'ctive to permit said traflio controlling device being controlledby said lever; and other means for. permitting control of said trafficcontrolling device by said lever which requires movement of said leverwhen traflic conditions are pro er comprising; a release relay whichmust e energized to permit control of said traflic controlling device bysaid lever, a stick relay which can only be picked up when traffic androute conditions are favorable and when said lever and said trafliccontrolling device assume corresponding positions and which will remainstuck up irrespective of whether said lever and traflic controllingdevice assume corresponding positions, a circuit for said release relayincluding a front contact of said stlck relay and contacts closed whensaid lever and said trafiic controlling device are outof correspondence,and two indicators one of which is rendered active when traific androute conditions are favorable and the other of which is rendered activewhen said lever and said traflic controlling device assumenoncorresponding positions. 7

11. In a centralized traific controlling system for railroads, a trackswitch, a switch machine for operating said track switch, a switchcontrol relay for governing'said switch machine, a control lever, apolarized control.

circuit connecting said switch control relay and said control lever,approach locking means associated with said track switch for preventingduring actuation of said means upon the passage of a train the operationof said switch control relay by said control lever, and means requiringsaid control lever to be in correspondence with said track switchsubsequent to the release of said approach looking means before saidcontrol lever can govern said switch control relay.

12. In a centralized traflic controlling system for railroads, a trackswitch, a control lever, operating means for operating said track switchwhen actuated by said control lever, locking means preventingactuationof said operating means during passage of a train over said trackswitch, and means requiring said control lever to be in correspondencewith said track switch subsequent to the passage of a train before saidogerating means can again be actuated by sai control lever 13. Incombination, a switch machine, a lever operated contact, a lock meansfor preventing operation of said switch machine, and a control circuitfor said switch machine including said lever o erated contact, saidcontrol circuit being e ective to cause. operation of said switchmachine only if said locking means is inactive at the time of closure ofsaid lever operated contact.

14. In combination, a distant track switch, a local lever forcontrolling the operation of said track switch, a relay for manifestingtraflic conditions, and means for preventing response of said trackswitch to aphange in the position of said lever when said relay 1sdeenergized and also preventing response of said track switch to suchchange in the position of said lever upon reenerglzation of said relayunless said lever is for a time placed into correspondence with saidtrack switch after such reenergization of said relay.

- 15. In combination, a distant tratfic controlling device, a locallever for controllingthe operation of said device, a relay formanifesting traflic conditions, and means ior preventing response ofsaid device to a change in the position of said lever when said relay isdeenergized and also preventing response of said device to such changein the position of said lever upon reenergization of said relay unlesssaid lever is for a time placed into correspondence with said deviceafter such reenergization of said relay. 16. In combination, a distanttrafiic controlling device, electro-responsive means for operating saiddevice, a lever for controlling said means, a relay for manifestingtraflic conditions, and means for preventing response of saidelectro-responsive means to a said lever and said electro-responsivedevice,

- ditions, and means for preventing response of said electro-responsivemeans to a change in' the'position of said lever when said relay isdeenergized and also reventin such response upon reenergization of sairelay unless said lever is for a time placed into COI'IQJ.

spondence with said device after such reenergization of said relay, andmeans for indicating the condition of energization of said relay.

19. In combination, a distant trafiic controlling device, operating saidevice, a lever for controlling said means, a relay for manifestingtrafiic conditions, means for preventing response-of saidelectro-responsive means to a change in the position of said lever whensaid relay is deenergized and also reventing such response uponreenergizatlon of said relay unless said lever is for a time placed intocorrespondence with said device after such reenergization of said relay,means for indicating when said lever and said electro-responsive deviceare out of corres ondence, and means for indicating the con ition ofenergization of said relay.

ectro-responsive means for ANDBEW LA GDON.

change in the position of said lever when said relay is deenergized andalso preventing such response upon reenergization of'said relay unlesssaid lever is for a time placed into correspondence with said deviceafter such reenergization of said relay.

17. In combination, a distant trafiic conv trolling device,electro-responsive means for operating said device, a lever forcontrolling said means, a relay for manifesting trafiic conditions,meansfor preventing response of said electro-responsive meansto a change inthe position of said lever when said relay is deenergized and alsopreventing such response upon reenergization of said relay unless saidlever is for a time placed into correspondence with said device aftersuch reenergization of said relav. and means for indicating when

